Power lift



Patented Dec. 28,

s PATENT for cs rownaur'rg.

Theophilur Brown, Molina, Ill.,

8: Company, Moline,

nois

Application November i i,

2 Claim!- (CL 97-60) The present invention relates generally to agricultural machines and more particularly to tractor-actuated power lift mechanisms by which various implement parts and/or tools may be lifted and raised or otherwise controlled by power derived from the tractor.

The object and general nature of the present invention is the provision of a power lift mechanism wherein one unit may be utilized for actuatingboth of a pair of implement'controlling movement.

another feature of this invention to provide biased valve controlling means for said individual units whereby either of said individual units may be operated independently of the main power lift mechanism.

These and other objects and advantages .of the present invention will be apparent to those skilled in the art after a consideration of the following detailed description, taken in conjunction with the accompanying drawing in which a preferred form of the present invention has been illustrated.

In the drawing: Figure l is a perspective view of the rear portion of a tractor in which power liftmcchanisms constructed according to the principles of the present invention has been incorporated;

Figure 2 is a fragmentary sectional view showing the manner of connecting one, of the implement controlling 'members with the transverse rock shaft of the main power lift mechanism; and

Figure 3 is a schematic diagram illustrating one way of effecting a hydraulic control for the individual power operated auxiliary units.

Referring now to the drawing, the reference numeral l indicates a farm tractor which comprises a combined crank case and supporting structure! to which a rear axle housing 3 is secured. The rear axle housing 3 includes latv el-ally directed housing sections 4 each of which is formed with an attaching boss 5, adapted to receive implements and other parts as desired. A hydraulic mechanism,v indicated in its entirety by the reference numeral 1, is bolted over the that in this position assignmto Deere acorporation of Illi- 1941, Serial No, 419,428

rear'opening of the axle housing '8 and preferably is of substantially the same construction as shown and claimed in United States Patent No. 2,107,760, issued February 8, 1938, to E. McCormick et al., to which reference may be had if desired. Briefly, the hydraulic mechanism I includes a pump unit 8, serving as a sourceof fluid pressure, driven by suitable connections to the power take-off shaft 8 extending rearwardly from the rear axle'housing and enclosed in a protecting tube 8. Preferably. the pump 8 is of the gear type and is enclosed within a housing H which forms a part of the hydraulic. power unit I. The upper part of the housing It is formed with lateral extensions l3 and in which a transverse rock shaft ii is mounted for rocking Disposed within the housing II is a. piston and cylinder unit oper'atlvely connected with the rock shaft i5 formoving the same from one position to another, substantially as disclosed in said priorpatent. Preferably, the outer ends of the rock shaft l5 are squared, and the rocking of the shaft I5 is under the control of valve mechanism that arm i8 extending laterally outwardly of the upper portion of the housing II. A trip lever I9 is mounted by suitable supports on the upper part of the housing II and is connected by a link 2| with the valve arm It. The trip lever is is secured to a rock shaft 22 about which a spring 23 is disposed. The left end of the shaft 22 carries a foot pedal 24, and the trip lever i9 is also formed with a second foot pedal 25. The spring 23- normally biases the trip lever 19 to take theposition shown in Figure 1, and the valve mechanism is so constructed and arranged the rock shaft I5 is per mitted to rock in a counterclockwise direction, as viewed from the right side of the machine, to its limit of movement. Stepping on either of the foot pedals 24 mechanism to cause the rock shaft to be rocked in a clockwise direction, this bein the raising movement of the rock shaft. Stepping on either of the foot pedals 24 and 25 a second time permits the rock shaft iiiv to return to its original of the rock shaft i5,

is actuated by a crank,

and 25 actuates' the valve cranks 3| and 32 are I provide a pair of rock shaft arms may be utilized for fixing 34 to the associated end present invention,

each piston as in mechanism is provided.

conventional construction and extension 36 that is adapted to engage one of the arms of the associated bell crank whereby rocking movement of the rock shaft IS in one direction causes the extensions 36 of the two lifting arms 34 to engage the associated bell cranks 3| and 32 so as to rock the bell cranks with the rock shaft l5. Any suitable means, such as a set screw 3'! each of the lifting aims of the rock shaft l5. For purposes of illustration, I have shown in Figure 1 a pair of cultivator lifting pipes 4| which normally extend along the sidesof the tractor for the purpose of lifting and lowering cultivator rigs connected with the tractor. The cultivator construction may be lik that shown in United States Patent No. 2,033,380, issued March 10, 1936, to Theodore W. Johnson. According to the the rear ends of the cultivator connected, as by pivot pins 42, to the upwardly extending arm 43 of the bell cranks 3| and 32. The bell cranks also have rearwardly extending arms 44 which carry studs 45. Each of the bell cranks 3| and 32 is mounted for rocking movement .on the ends of the rock shaft l5 by the means shown in Figure 2 and described above. The lifting extension 36of each lifting arm 34 contacts the rearwardly extend: ing bell crank arm 44, as best shown in Figure 1. A pair of auxiliary hydraulic units, each indicated in its entirety by the reference numeral 50 in Figure 1, is mounted on the rear axle 3. To this end, each of the auxiliary hydraulic units includes a casing 5| having a lateral extension 52 apertured to receive attaching studs 53 that are threaded into tapped openings in the rear axle attaching p ds or bosses 5. The two housings 5| are substantially identical except that one is a right-hand unit and the other is a lefthand unit, and each is formed with a cylinder disposed generally vertically in which a piston moves, there being a piston rod 51 connected to conventional construction. In Figure 3, the piston is indicated by the reference numeral 56. Each housing 5| also includes a valve chamber indicated in its entirety by the. reference numeral 6| in which suitable valve The hydraulic units 5|? push pipes 4| are are of generally hence it is not necessary to show the particular parts thereof. in detail. It will be sufficient to note from Figure 3 that the valve mechanism 63 includes a passage 6| leading to the bottom of the cylinder 5|, a high pressure passage 52 and a low premure passage 63. As best shown in Figure 1, these passages are connected through conduits 64 and 65 with the tractor power lift mechanism I, the low pressure conduits 65 communicating with the sump of the tractor power lift mechanism, which is formed in a housing II! that forms a part of the tractor power lift I. A pair of separate pumps 8:: and 8b are provided, both connected with the power take-off shaft 6. One of the conduits 64 lead to the high pressure side of the pump 8a and the other conduit 64 leads to the high pressure side of the other pump 8b, as shown in Figure'l. Each of the separate units 68 includes a cont o ng valve which is frail-- cated in Figure 3 .by the reference numeral It and is operated by a rod 72 that extends outwardly of the casing of the valve mechanism 60.

Each of the valve mechanisms Gil is controlled by a separate lever, indicated in Figure 1 by the reference numeral 15.

the rock shaft housing extension at that side of the tractor. A valve operating armis is fixed to each rock shaft 16 and has its outer end connected with the associated valve operating rod 12. An arm 8| is fixed to each of the rock shafts l6 and is connected to a pair of springs 82 and 83, the outer ends of which are anchored to lugs 84 and 85 carried by the rock' shaft housing extension. The purpose of the two springs 82 and 83 is to hold the associated valve member I! in neutral position, which is the position shown in Figure 3. v

The operation of the construction described above is as follows.

When the farmer desires to raise both of the cultivator rigs associated with the push pipes 4|, he steps on either of the foot pedals 24 and 25, which actuates the power lift mechanism 1 and causes the rock shaft l5 to rock in a clockwise direction, thereby swinging both of the bell cranks 3| and 32 in that direction and pushing forwardly on both of the push pipes 4|. When the former desires to lower both of the cultivator rigs, he again steps on either of the foot pedals 24 and 25, and the weight of the cultivator rigs causes them to move downwardly, the push pipes 4| moving rearwardly and both of the bell cranks 3| and 32 swinging in a counterclockwise direction. The amount of swinging movement of the 'bell cranks 3i and 32 in this direction is determined by the positions of the piston rods 51 of the hydraulic auxiliary units to, That is, each bell crank swings in a counterclockwise direction until the stud engages the bottom of the slot 59 in the associated link 58-. In other words, the auxiliary hydraulic units serve as individual stops for separately controlling the lowered or return position of the two bell cranks 3| and 32. Considering these auxiliary units as stops, they are adjustable, both when; the bell cranks are rocked Gland 63 and opening This levelis fixed to a shaft TIE that is supported, as by brackets [Lon in a clockwise direction to raise the cultivator rigs and when the rigs are in their lowered position, with the pins 45 resting in the bottoms of the slots 59. To adjust the lowered position of either rig, all that the operator has to do is to move the valve lever 15 of the associated auxiliaryhydraulic unit in one direction or the other, according to whether it is desired to increase or decrease the penetration of the rigs. For example, assume that it is desired to raise the pic ton 5i of the right-hand hydraulic unit to (Fig ure 1) the operator pushes forward on the valve control lever 75, and this raises the valve link 12, which turns the valve 1| closing 01f communication between the high and low pressure passages communication between the high pressure passage 62 and the passage 68 leading to the cylinder 5|. This causes fluid to be directed into the cylinder and raises the piston and piston rod 61, thereby raising the associated link 58. When the latter has been raised to the desired extent, the farmer returns the level: to its neutral position, which again opens commlmication between the high and low pressure between the cylinder passage 6| and the low pressure passage 53, the high pressure passage 62 also communicating with the low pressure passage 63.

The weight of the parts then causes the piston to move downwardly in the cylinder to the desired point. at which iimethe tanner returns the valve lever Vito neutral position which 2,887,687 locks the remaining fluid in the cylinder and maintains communication between the high and low pressure passages. Ordinarily, all that the farmer has to do to return the valve lever I to neutral position is to release it, since the springs 82 and 83 act to hold the valve lever in neutral position and therefore also act to return it automatically to neutral position whenever the valve lever is released. i

It will be noted that the two auxiliary hydraulic units 50 serve as independent means separately controlling the bell cranks 3| and 32.

Also, it will be noted that the hydrauic .units 50 may be utilized as means for raisingboth of the cultivator rigs instead of the tractor power lift mechanism 1, and this may be done by moving both of the valve levers forwardly. Moreover, the tractor power lift mechanism I may be actuated to swing both of the bell cranks 3| and 32 forwardly, and then, if it should be desired subsequently to lower only one of the cultivator rigs, the hydraulic unit 50 associated with the other rig may be actuated by moving its valve lever I5 forwardly to raise the piston 51 of that unit through its full extent, whereby when the hydraulic power lift unit I5 is operated to permit the rock shaft I5 to rock rearwardly, only the other cultivator unit will be lowered, and its position will be determined by the position of the other auxiliary hydraulic unit 50. Then, the first cultivator rig may subsequently be lowered by moving the valve lever I5 of the associated auxiliary hydraulic unit rearwardly, thus permitting the rig to lower to the desired point. From this it will be seen that the present invention is admirably adapted to secure what is termed a delayed lift control for cultivator rigs or other tools, which is an advantage when operating on point rows. The provision of the auxiliary hydraulic units also makes it possible for the farmer to raise the cultivator rigs or other tools as slowly as desired, as by opening the valves only a small amount. It will be understood, of course, that the present invention is not necessarily limited to the control of cultivator rigs, since any other tools that may be connected with the bell cranks 3| and 32 may be controlled in a similar manner. For example, two-way plows may be mounted on the tractor and controlled individually by the auxiliary hydraulic units 50. i

' While I have shown and described above in connection with the accompanying drawing the preferred form of the present invention, it is to be understood that my invention is not to be limited to the particular details shown and described above, but that, in fact,'widely difierent means maybe employed in the practice of the broader aspects of my invention.

What I claim, therefore, and desire to secure by Letters Patent is:

1. In an agricultural machine having a source of power, a pair of tool moving members, power means deriving power from said source for moving both of said members at the same time, and

separate power means including a pair of separate pumps and separately. actuable controlling valve units, one for each of said pumps, for moving said members individually.

2'. A tractor comprising a power take-off shaft and a power operated hydraulic unit, a transverse rock shaft adapted to be rocked in at least one direction by said power unit, operating mem-' bers having a one-way connection with said transverse rock shaft whereby movement of the latter in one direction actuates said members, and a pair of hydraulic units, each including a pump driven from said power take-off shaft, for

separately controlling said members.

THEOPBILUS BROWN. 

